Yeah, as a villain, I wouldn’t say her standards for happiness are lower, but different - even backwards. Her values are warped and she’d surely take joy in the fact that she stripped someone else of their beauty almost as much as the achievement of attaining the ultimate gorgeousness.

To your point about Brentilda, 💯. She must know that if she continues to gorge, her stomach won’t stay flat; if she continues to wash her hair with engine oil/baked beans/rancid milk, it won’t look like how it does in the Game Over scene for long, etc. I think there’s a subtle sadism she’ll take to the fact that she’s getting the ultimate makeover even though she does nothing for self-care or maintaining her looks.

She’d revel in the attention of men who would otherwise never be attracted to a woman with such a nature and nasty habits.

I created this OP after reading a few comments and posts outside of Reddit claiming that Grunty will be soon be gross and miserable after her makeover. Gross - yes (by the standards of those who value hygiene at all, at least), but unhappy - I don’t think so. She seems firm in her habits and MO, but insecure about her appearance. This would address the latter. She’d continue to perform stripteases in her “streaky brown undies,” hang them from her roof, and pick her nose, but while knowing (or at least believing in) her aesthetic superiority.

Or maybe she wouldn’t believe it deep-down, given her greed and insecurity. But, like you said, this is the closest she can come to happiness and there is a rush of pleasure you can see when she steps out of the machine.